Portlet specification specifies several different portlet request types
Render - Renders html
Action - Performs an action
Resource - Serves any kind of resource (documents, json, html, ... )
Resource is the way you go for what you ask.
If you are using
MVCPortlet , you can override the empty method :
void serveResource(ResourceRequest resourceRequest, ResourceResponse resourceResponse)
which writes in the ResourceResponse in the same way you would do for a HttpServletResponse, and will be accessible as a Rest service.
Then in the JSP (if you are using jsp for rendering your page), you can use the portlet:resourceURL taglib or liferay-portlet:resourceURL using the resourceId (identifies uniquely the serveResource operation) to create the URL to call the server thought this rest service you have just created.
DWR is much complex for him, as he didn't yet know what "serveResource" means. Don't think this is what he is looking for.
